摘要
采用不同水蒸气处理温度制备了一系列HZSM-5分子筛,考察了其催化甲醇脱水反应的性能,并以其为甲醇脱水活性组分与铜基甲醇合成活性组分(Cu-ZnO-Al2O3)组成双功能催化剂,考察了其对合成气直接制二甲醚反应的催化性能。结果表明,随着水蒸气处理温度的提高,HZSM-5分子筛的酸性逐渐减弱,从而使甲醇脱水反应的二甲醚选择性逐渐增大。对于催化合成气直接制二甲醚反应,当HZSM-5分子筛在适当温度(500℃)下进行处理时,可使反应产物中CO2副产物的选择性明显下降,目的产物二甲醚的选择性显著提高。当处理温度过高(600℃)时,CO的转化率和二甲醚的选择性均明显降低。相同温度下的水蒸气和氨水蒸气处理对Cu-ZnO-Al2O3/HZSM-5双功能催化剂催化合成气直接制二甲醚反应的性能几乎无影响。
A series of HZSM-5 zeolites were prepared by steam treatment at different temperatures,and their catalytic performances for methanol dehydration were investigated.Moreover,the prepared HZSM-5 zeolites were physically mixed with a methanol synthesis component（CuO-ZnO-Al2O3） to form hybrid catalysts,and their catalytic performances for the direct synthesis of dimethyl ether（DME） from syngas were studied.The results indicated that the selectivity for DME in the methanol dehydration increased with the increase of steam treatment temperature of HZSM-5 due to the decrease of the acidity in HZSM-5 zeolites.In the direct synthesis of DME from syngas process over the hybrid catalysts with the HZSM-5 steam treated at proper temperature（500℃）,the selectivity for undesired CO2 decreased,so the selectivity for DME was enhanced significantly,while with the HZSM-5 steam treated at 600℃,both the CO conversion and DME selectivity were decreased remarkably.No difference in the catalytic performance of the hybrid catalysts was observed with the ammonia treatment and steam treatment of HZSM-5 zeolite.
出处
《石油学报（石油加工）》
EI
CAS
CSCD
北大核心
2011年第6期897-903,共7页
Acta Petrolei Sinica(Petroleum Processing Section)
基金
上海市科委地方能力建设项目(08520513600)
上海市教委重点学科建设项目(J51503)资助
